Department of Pharmaceutical Chemistry, The Islamia University of Bahawalpur, Bahawalpur, Pakistan.
Department of Chemistry, D.G. Khan Campus University of Education, Lahore, Pakistan.
PLoS One. 2022 Mar 31;17(3):e0266094. doi: 10.1371/journal.pone.0266094. eCollection 2022.
Owing to extraordinary healing power, Terminalia species have been used in traditional medicine systems to treat various diseases. Many folklore uses of Terminalia neotaliala (Madagascar's almond) included treating arterial hypertension, diabetes, diarrhea, dysentery, colic, oral and digestive candidiasis, intestinal parasitic infections, inflammatory skin conditions, postpartum care, and mycotic infections but nevertheless scientifically explored for its medicinal and pharmacological importance. Therefore, the current study intended to prepare methanolic extract and its fractionation with hexane, chloroform, and butanol followed by evaluation of their polyphenolic content, biological activities, and LCMS analysis. The biological study included antioxidant activity and enzyme inhibition assay i.e., α-glucosidase and urease. The insight study of biologically active secondary metabolites of butanol fraction (BUAE) was performed through LCMS.
The total phenolic content (TPC) and total flavonoid content (TFC) of hydroalcoholic and its fractions were estimated using the Folin-Ciocalteu and aluminum chloride method. The total tannin content (TTC) was determined using the Folin-Denis spectrophotometric method. Similarly, the antioxidant potential of HAAE, HEAE, CFAE, and BUAE was determined using four methods as DPPH (1,1-diphenyl-2-picrylhydrazyl), 2,2-azinobis(3-ethylbenothiazoline)-6-sulfonic acid, cupric reducing antioxidant capacity (CUPRAC), and ferric reducing antioxidant power (FRAP). The sample extracts were also evaluated against two clinically important enzymes i.e., α-glucosidase and urease.
The BUAE (butanol aerial fraction) showed the highest TPC (234.79 ± 0.12 mg.GAE.g-1 DE), TFC (320.75 ± 12.50 mg.QE.g-1 DE), and TTC (143.36 ± 4.32 mg.TA.Eq.g-1 DE). The BUAE also showed the highest scavenging potential determined by DPPH (642.65 ± 1.11 mg.TEq.g-1 DE) and ABTS (543.17 ± 1.11 mg.TEq.g-1 DE), and the metal-reducing capacity determined by CUPRAC (1510.41 ± 4.45 mg.TEq.g-1 DE) and FRAP (739.81 ± 19.32 mg.TEq.g-1 DE). The LCMS of BUAE identified 18 different biologically active phytoconstituents validating a rich source of hydrolyzable tannins including ellagitannins and gallitannins.
The present study concluded that T. neotaliala is a rich source of polyphenols capable of neutralizing the damage caused by free radical accumulation in the cells and tissues. The significant antioxidant results and identification of high molecular weight hydrolyzable tannins enlightened the medicinal importance of T. neotaliala.
由于 Terminalia 物种具有非凡的愈合能力，因此在传统医学系统中被用于治疗各种疾病。Terminalia neotaliala（马达加斯加杏仁）的许多民间用途包括治疗动脉高血压、糖尿病、腹泻、痢疾、绞痛、口腔和消化性念珠菌病、肠道寄生虫感染、炎症性皮肤病、产后护理和真菌感染，但仍在医学和药理学方面进行了科学探索。因此，本研究旨在制备 Terminalia neotaliala 的甲醇提取物及其正己烷、氯仿和正丁醇部分，并评估其多酚含量、生物活性和 LCMS 分析。生物研究包括抗氧化活性和酶抑制测定，即α-葡萄糖苷酶和脲酶。通过 LCMS 对正丁醇部分（BUAE）的生物活性次生代谢物进行了深入研究。
使用 Folin-Ciocalteu 和三氯化铝法测定水醇提取物及其各部分的总酚含量（TPC）和总黄酮含量（TFC）。使用 Folin-Denis 分光光度法测定总单宁含量（TTC）。同样，使用 DPPH（1,1-二苯基-2-苦基肼）、2,2-联氮双（3-乙基苯并噻唑啉-6-磺酸）、铜还原抗氧化能力（CUPRAC）和铁还原抗氧化能力（FRAP）四种方法测定 HAAE、HEAE、CFAE 和 BUAE 的抗氧化潜力。还评估了样品提取物对两种临床重要的酶，即α-葡萄糖苷酶和脲酶的抑制作用。
BUAE（正丁醇空中部分）表现出最高的 TPC（234.79±0.12mg.GAE.g-1 DE）、TFC（320.75±12.50mg.QE.g-1 DE）和 TTC（143.36±4.32mg.TA.Eq.g-1 DE）。BUAE 还表现出最高的 DPPH（642.65±1.11mg.TEq.g-1 DE）和 ABTS（543.17±1.11mg.TEq.g-1 DE）清除能力，以及 CUPRAC（1510.41±4.45mg.TEq.g-1 DE）和 FRAP（739.81±19.32mg.TEq.g-1 DE）的金属还原能力。BUAE 的 LCMS 鉴定出 18 种不同的生物活性植物成分，验证了其是水解单宁（包括鞣花单宁和没食子单宁）的丰富来源。
本研究得出结论，T. neotaliala 是多酚的丰富来源，能够中和自由基在细胞和组织中积累造成的损害。显著的抗氧化结果和对高分子量水解单宁的鉴定，说明了 T. neotaliala 的药用重要性。
